There are those who believe the bombs and blood were staged, that the amputees and others injured were actors in some kind of Hollywood production designed to justify martial law. Others acknowledge the carnage but say it was perpetrated by a secret squad of special operations soldiers. And there are those who insist that inconsistencies in early reports, erroneous statements by public officials, and unreleased evidence from prosecutors – among other things – reflect anything from a government cover-up to an effort to frame the suspects.

Three months after two bombs detonated near the finish line of the Boston Marathon, killing three and injuring more than 260, skeptics and conspiracy theorists from around the world have coalesced on Facebook, Twitter, and elsewhere – including at an acrimonious appearance this month in federal court – to defend Dzhokhar Tsarnaev.